The present invention relates to a motor-driven compressor having a shell receiving therein an electric motor that is electrically connected to a power source located outside the shell.
In such kind of compressor, a first conductor connected to the power source extends through the shell, and a second conductor connected to the electric motor is connected to the first conductor in the shell.
Due to the stop of the compressor for a long time, refrigerant gas existing in the compressor or within the shell may be cooled and liquefied, and such liquefied refrigerant may remain in the compressor. Although the second conductor is covered by an insulator, immersion of the connection between the first and second conductors in the liquid refrigerant may cause electrical leakage between the first and second conductors.
In the compressor disclosed in Japanese Unexamined Patent Application Publication No. 5-256261, the second conductor or a motor lead wire is connected to a spring terminal, and part of the first conductor that is located in the shell is inserted in the spring terminal and electrically connected thereto. The spring terminal is covered by a heat-shrink tube in the shell. The tube shrinks when heated by operation of the compressor, thereby preventing contact between the conductors and liquid refrigerant in the shell.
However, sealing provided by the shrinkage of the tube may be insufficient and, therefore, electrical leakage in the shell may possibly occur. Good sealing may be accomplished, for example, by covering the spring terminal using heat-hardening resin such as epoxy resin and then setting the resin by heating. However, this procedure is troublesome.
The present invention is directed to providing a motor-driven compressor that provides improved and simple sealing of electrical connection between a first and a second conductors in a shell of the compressor.